Casing tester



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F. F. WALTERMIRE cAsING TESTER Filed July 22, 1958 @si I.,

Jam 27, 1.939.

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AT ORNEY Patented June 27, 1939 UNITED STATES casino. 'rus'rea Fred Flynn walmire, Houston, Tex., signor to Continental Oil Company, Ponca City.

Okla., a corporation of Delaware ApplicatlonhJuly 22, 1938, Serial No. 220,706'

4 Claims.

My invention relates to a casing tester. In the drilling of oil wells in which casing is placed, the rotation of the drill pipe may wear through or puncture the casing. A leak may occur in the casing due to a faulty joint, faulty cementing, or by accident during the removal of tools. `A leaky casing will result in the loss of valuable gas pressure and oil. The loss of gas under high pressures could cause the well to crater.

One object of my invention is to provide an apparatus for testing oil well casing.

Another object of my invention is to provide a means for determining that an oil well casing is tight and free from leaks in order to preclude blowouts, and damage or danger from the leakage of gas.

In the accompanying drawing which forms part of the instant specification and which is to be read in conjunction therewith, and in which like reference numerals are used to indicate like parts in the various views,

Fig. 1 is a sectional view of a well fitted with a casing tester of my invention.

Fig. 2 is an enlarged sectional view of my casing tester in position in the well casing.

Fig. 3 is a sectional view taken on the line 3 3, Fig. 2. v

More particularly, referring now to the drawing, a well casing I is provided with a casing head 2 of any suitable design, and provided with packing means 3 adapted to pack a drill pipe 4, to the lower end of which my casing ,tester 5 is secured. The casing tester comprises a body portion 6, an expandible packer 1, and avalve 8 adapted to seat upona valve seat 9.

The valve 8 is provided with a valve stem I0, provided with guide members l I. The valve stem terminates in a mushroom head I2.

When it is desired to test a casing which has been landed and cemented in a well, the testing device is run in the well inside the casing to the desired depth, carried screwed to the bottom of a string of drill pipe 4. 'I'he valve assembly comprising valve 8, the valve stem and the valve head, is not inserted inthe tool when running the drill pipe intolthe well. This is to permit the circulation of water or drilling fluid, if desired.

After the testing tool has been desired depth, the blowout preventer I3, containing the sealing means 3, is closed around the drill pipe, making a tight seal between it and the casing to be tested. The valveldart is then dropped into the drill pipe from the derrick floor, being guided by the guide members Il. It falls to its lowered to the seat 9 on the bottom of the testing tool, closing the opening I4 through the body 6. Any suitable fluid, such as compressed air, water, drill ing mud, or the like, is then pumped through the drill pipe from the surface. .This builds up s pressure inside the expandible rubber packer 'Il and causes it to seal against the casing, it being understood vthat eduction pipes I6 andll leading from the casing are closed by suitable valves (not shown). Fluid will then escape as shown l0 by the arrows through the ports I5, building up pressure within the casing. Pressure of any desired magnitude may be built up and held. A leak is determined by a drop in pressure over a period of time, as will readily be understood by l5 those skilled in the art. If a leak is discovered, the valves controlling .the pipes I6 andl II are opened relieving the pressure. The valve dart is then removed by an extracting tool shown in dotted lines in Fig. 2. This extracting tool is zo well known to the art and is similar to that used for retrieving core barrels. The extracting tool is. adapted to grip mushroom head I2 pulling the valve from its seat and permitting the pressure -within the expandible packer 1 to escape, thus 25 collapsing the packer. The `drill pipe is then lifted a predetermined distance and the test run again. If a leak still occurs, it is known that the leak is between the top of the casing and the point at which the packer was last positioned. 30 The procedure is repeated until the packer is removed to a place above that where the last leakage was noted and the leak is thus located.

It may be then repaired by cementing or the like, and the casing again tested. It will be seen that I have accomplished the objects of my invention. I have provided a casing tester tool which may conveniently and expeditiously locate leaks within oil well casings. It is extremely important to have a tight casing Where it is known that 4gas under high pressure will be encountered. The leakage of such gas from a. casing may cause serious blowouts, often resulting in the loss of the well. Then, too, such gas leakage with the resultant formation of craters presents a distinct fire hazard.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and sub-combinations. 'Ihis is contemplated by and 50 is within the scope of my claims. It is further obvious that various changes may be made in details within the scope of my claims without departing from the spirit of my invention. It is, therefore, to be understood that my invention is u not to be limited to the speciilc details shown and dcribed.

Having thus described my invention, I claim:

l. A casing tester comprising in combination a body member, means for securing the body member to a pipe adapted to be inserted within a casing to be tested, fluid pressure expandible packing means carried by said body member, said body member being formed with a bore, a valve seat formed in said bore, a valve adapted to be seated upon said seat, means providing communication between said bore and said packing means, means above said last named communicating means and providing communication between said bore and the well casing, said valve being formed with means permitting its removal iromsaid seat from the surface of the well.

2. A casing tester as in claim 1 in which said valve is formed with guide means permitting its dropping from the surface to seating position through said pipe.

3. An oii well casing testing assembly including in combination a casing to be tested, a pipe housed within the casing to be tested, a body member carried by the lower end of said pipe, means for sealing the pipe and the upper end of the casing, said body member being provided with iiuid pressure expandible packing means adapted to seal against said casing, means providing communicatlon between said pipe and said expandible packing means, and means providing communication between said pipe and the annular space between the pipe and the casing above said packing means.

4. An oil well casing testing assembly includlng in combination a casing to be tested, a pipe housed within the casing to be tested, a body member carried by the lower end of said pipe, means for sealing the, pipe and the upper end of the casing, said body member being provided with uid pressure expandibie packing means adapted to seal against said casing, means providing com.'- munication between said pipe and said expandible packing means, means providing communication between said pipe and the annular space between the pipe and the casing above said packing means, means providing communication between said pipes and said casing below said packing means, and a valve operable from the surface for selectively closing said last named communicating means.

FRED FLYNN WALTERMIRE. 

